Multiple piston expansion chamber engine

Abstract

Multiple expansion chambers are configured to partially expand the combusted charge in the combustion chamber and then to complete the expansion process using a supplemental expansion chamber with chamber isolation designs.

I claim: 
     
       1. An internal combustion engine wherein combustion, expansion and exhaust functions are performed in a cylinder comprised of an auxiliary piston reciprocating in the cylinder, a sleeve valve reciprocating within said auxiliary piston, a working piston reciprocating within said sleeve valve and leading said auxiliary piston, an auxiliary chamber above said auxiliary piston and a combustion chamber above said working piston; said sleeve valve controlling communication of said auxiliary chamber with said combustion chamber to prevent communication of combusted products from the chamber above said working piston to the chamber above said auxiliary piston from when the working piston is at about TDC until a subsequent expansion stroke of said working piston is underway and at a point between 30 and 160 degrees past TDC and with said auxiliary piston being at about TDC at this same instant when said working piston is at said point and said communication then is commenced; and to permit communication only during said expansion stroke continuing past said point and a following exhaust stroke of said working piston so as to utilize energy of expansion from said auxiliary piston as it expands until said working piston has passed through BDC and returns to about TDC during said exhaust stroke of said working piston. 
     
     
       2. An internal combustion engine according to claim 1: wherein said communication controlling means comprises a sealing surface on a surface of said (auxiliary) sleeve valve adjacent said working piston. 
     
     
       3. An internal combustion engine according to claim 1: wherein said communication controlling means comprises a circular sealing surface on an (upper) upward viewing surface of said auxiliary valve adjacent said working piston. 
     
     
       4. An internal combustion engine according to claim 1: wherein said sleeve valve is around said working piston sealing on inner surface of said sleeve valve adjacent said working piston with multiple sleeve valve projections to contain rings as the sleeve valve is withdrawn during communication.